Yazar "Can, Orhan Taner" seçeneğine göre listele
Listeleniyor 1 - 13 / 13
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Anodic oxidation of bisphenol A by different dimensionally stable electrodes(IWA Publishing, 2021) Can, Orhan Taner; Tutun M.M.; Keyikoglu R.Bisphenol A (BPA) is a known endocrine disrupter and was detected in surface waters. This study investigated the mineralization of BPA by electrochemical oxidation using different anode materials including boron-doped diamond (BDD), platinum, and mixed metal oxide (MMO) electrodes (RuO2-IrO2, RuO2-TiO2, IrO2-Ta2O5, and Pt-IrO2). These electrodes were compared in terms of BPA mineralization efficiencies and electrical energy consumptions. Total organic carbon (TOC) was analyzed to monitor the mineralization efficiency of BPA. BDD achieved 100% BPA mineralization efficiency in 180 min and at a current density of 125 mA/sq cm, whereas the TOC removal efficiency of Pt was 60.9% and the efficiency of MMO electrodes ranged between 48% and 54%. BDD exhibited much lower specific energy consumption, which corresponds to a lower energy cost. The effect of operational parameters showed that the BDD anode was much more affected by the current density, initial BPA concentration, and electrolyte concentration than the other parameters such as the stirring speed and interelectrode distance.Öğe Anodic Oxidation of Effluents from Stages of MBR-UF Municipal Landfill Leachate Treatment Plant(Mary Ann Liebert, Inc, 2020) Ukundimana, Zubeda; Kobya, Mehmet; Omwene, Philip Isaac; Gengec, Erhan; Can, Orhan TanerThis study used boron-doped diamond electrode on niobium substrate (Nb/boron-doped diamond [BDD]) for the anodic oxidation of landfill leachate in a batch reactor. Raw leachate and biologically pretreated effluent samples were collected from each step of the existing unit operation of a municipal landfill leachate treatment plant (Kocaeli-Turkey). The influence of parameters, such as treatment time, initial pH (3.50-10.0), and applied current density (j = 76-1,060 A/m(2)), on the removal of total organic carbon (TOC), chemical oxygen demand (COD), and ammonium nitrogen (NH4+-N) was assessed. The highest pollutant removal efficiencies were obtained at leachate inherent pH (6.50-8.75), moreover, pollutant removal rates increased with the increase in current density. The NH4+-N removal mainly occurred by indirect oxidation and well fitted second-order kinetics, whereas COD removal followed pseudo first-order kinetics. The optimum current density ensuring simultaneous removal of COD and NH4+-N was 756 and 455 A/m(2)for raw leachate and for pretreated effluents, respectively. Under these optimums, nearly complete NH4+-N removal was attained, while >= 97% removal of TOC and COD was recorded. Herein, we present anodic oxidation as a suitable alternative for treatment of both stabilized raw leachate and effluents from stages of the membrane bioreactor/ultrafiltration treatment plant for the abatement of COD, TOC, and NH4+-N.Öğe Comparison of the effects of various supporting electrolytes on the treatment of a dye solution by electrocoagulation process(Elsevier, 2019) Keyikoğlu, Ramazan; Can, Orhan Taner; Aygün, Ahmet; Tek, AhuLaboratory experiments were conducted to investigate the effect of some supporting electrolytes on the treatment of Reactive Black 5 (RB5) by electrocoagulation using aluminum and iron electrode couples. Electrolytes, which contain Cl-, SO42-, NO- anions and Na+, K+, NH4+ cations, were compared in terms of color removal efficiencies. The presence of SO42- led to poor performances with aluminum electrodes yielding a removal efficiency close to 45% at 8.33 A/m(2). Similarly, the presence of NO3- when iron electrodes were used adversely affected the process performance. The removal efficiency with KNO3 was 49.1% at 8.33 A/m(2). Overall Cl- containing electrolytes performed well achieving almost complete decolorization (99.9%) regardless of the electrode type. The performance of Al electrode considerably improved in the presence of NH4+, achieving 98.0% and 99.1% removal efficiencies at the current densities of 4.17 A/m(2) and 8.33 A/m(2), respectively in 10 min treatment duration.Öğe Electrocoagulation for nitrate removal in groundwater of intensive agricultural region: a case study of Harran plain, Turkey(Springer Science and Business Media Deutschland GmbH, 2021) Yazici Karabulut, B.; Atasoy, A.D.; Can, Orhan Taner; Yesilnacar, M.I.This study focuses on the mechanism of Nitrate (NO3?) removal from aqueous solutions by electrocoagulation (EC) using aluminum (Al) and iron (Fe) electrodes and on the reduction of high nitrate levels in the groundwater of an arid/semi-arid region. Influence of initial pH, varying electrode material, inter-electrode distance, initial conductivity, and nitrate concentration over percentage removal of nitrate as well as energy consumption were all studied. The process was carried out by batch method at room temperature (25 °C). Tests were performed on a synthetic water sample prepared in the laboratory and ten samples collected from the Harran Plain region. According to the results of experimental studies, optimum experimental conditions were found to be with Al electrodes and initial pH = 6, run time = 210 min, current density = 2.31 A/m2, inter-electrode distance = 10 mm, and conductivity = 1000 µs/cm for removal of 80.1% nitrate (initial concentration = 250 mg/L). The energy consumption for experimental setup and real groundwater were 2.07 kWh/m3 and 1.925 kWh/m3, respectively. As the Al electrode distance was increased from 10 to 20 mm, the percentage of nitrate removal decreased from 80.1 to 62.3% because of the decrease in electrostatic attraction. It was found that Fe electrodes did not have a significant effect on nitrate removal (12.4%). The removal efficiency of Ugurlu groundwater that has the highest nitrate concentration was found to be 62.0% for Al electrode and 39.0% for Fe electrode. The Al-Al electrode combination used in the studies yielded better efficiency than the Fe–Fe electrode combination. It is thought that this method will also be applicable to regions with the same characteristics as the arid/semi-arid study region. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.Öğe Electrooxidation as post treatment of ultrafiltration effluent in a landfill leachate MBR treatment plant: Effects of BDD, Pt and DSA anode types(Pergamon-Elsevier Science Ltd, 2018) Ukundimana, Z.; Omwene, P., I; Gengec, E.; Can, Orhan Taner; Kobya, M.In this study, ultrafiltration (UF) effluent from a landfill leachate treatment plant (equipped with anoxicaerobic oxidation and UF) was treated by Electrooxidation (EO) process in a batch reactor using different dimensionally stable electrodes (DSA anodes: Ti/PtO2-IrO2, Ti/RuO2-TiO2, Ti/RuO2-IrO2, and Ti/IrO2-Ta2O5), boron doped diamond (BDD) and Pt as anode and stainless-steel electrode as cathode. The untreated UF effluent had COD and TOC concentrations of 888 mg/L and 398.6 mg/L, respectively. Overall, BDD anode performed better than the other DSA anodes under the tested conditions with removal efficiencies of 64.9-86.8% and 68.2-92.0% for TOC and COD, respectively. The calculated energy consumptions at maximum removal efficiencies were 111.2 kWh per m(3) (136.01 kWh/kg COD and 321.27 kWh/kg TOC) at 360 A/m(2) and 4 h of treatment time for BDD anode. However, TOC and COD removal efficiencies of 31.3-86.8% and 36.5-92.0%, respectively, were obtained for the other DSA anodes at current densities between 60 and 360 A/m(2) and 4 h of treatment time. Energy consumptions and anode efficiency for DSA anodes ranged from 7.3-111.2 kWh/m(3) (15.67-194.87 kWh/kg COD) and 4.40-34.24 g COD/Ah m(2) (or 1.77-14.62 g TOC/Ah m(2)). The general COD and TOC removal mechanism well fitted the pseudo first-order kinetic model with R-2 of >0.94 particularly for BDD electrode under all applied current densities. The chloride content in the leachate promoted indirect oxidation leading to higher COD and TOC removal efficiencies. Moreover, high performance size exclusion chromatography (HPSEC) was used to evaluate the variation of fractions in wastewater during EO. (C) 2018 Published by Elsevier Ltd.Öğe Elektrokoagülasyon Yöntemi ile Sulardan Boyarmadde Gideriminde Molekül Büyüklüğü ve pH etkisi(2017) Gazigil, Leyla; Can, Orhan TanerElektrokoagülasyon koloitlerin atıksulardan giderilmesinde kullanılan önemli arıtma yöntemlerinden biridir. Boyarmaddeler atıksulardaki önemli koloit kaynaklarının başında gelirler. Tekstil endüstrisinde oldukça fazla kullanılan boyarmaddeler, endüstrinin kullandığı su miktarının fazlalığı da göz önüne alındığında alıcı su ortamları için önemli kolloidal kirleticiler haline gelirler. Bu çalışmada farklı molekül ağırlığındaki iki ayrı tekstil boyar maddesi kullanılarak kirletici koloitlerin molekül ağırlığının elektrokoagülasyonda giderme verimine ne şekilde etki ettiği incelendi. Bu amaçla alüminyum elektrotların kullanıldığı reaktöründe renk giderme çalışmaları yapıldı. Çalışma farklı pH değerlerinde yapılarak farklı flok yapılarının (büyüklüklerinin) etkileri de incelendi. pH artışından daha büyük molekül ağırlığına sahip olan boyarmadde daha çok etkilendiği tespit edildi. Boyarmadde gidermede daha büyük molekül ağırlığına sahip olan Reactive Black 39 (1021.16 g/mol) pH değişiminden % 100 'den 74.83 'e düşüşle, yaklaşık % 25 oranında etkilenirken, daha küçük molekül ağırlığına sahip olan Remazol Red 3B (674.10 g/mol) % 96.54 'den 83.01 'e düşüşle yaklaşık % 13 oranında etkilenmektedir.Öğe Mineralization of o-tolidine by electrooxidation with BDD, Ti/Pt and MMO anodes(Desalination Publ, 2019) Can, Orhan Taner; Bayramoglu, Mahmut; Sozbir, Mustafa; Aras, OmurThe present study deals with the electrooxidative mineralization of o-tolidine from aqueous solution using various Ti/Pt, mixed metal oxide (MMO) and boron doped diamond (BDD) anodes. The experiments were carried out in two phases. In the first phase, the effect of anode type on the total organic carbon (TOC) removal efficiency was investigated at various pH levels. Furthermore, the second phase was carried out with the most effective anode, to investigate the effects of various operating parameters on the TOC removal efficiency, such as current density, stirring speed, inter electrode distance, concentrations of o-tolidine and the electrolyte. Also, specific energy consumption (SEC) based on the amount of electricity consumed for TOC removal was estimated. The results showed that BDD anode was much more efficient than Ti/Pt and MMO anodes for the mineralization of o-tolidine. The current density and stirring speed were the most effective parameters. With BDD anode, TOC removal efficiency realized as 54.6% and 79.9% for the current density of 25 mA/cm(2) and 125 mA/cm(2) respectively, at 150 min of processing time. On the other hand, TOC removal efficiency realized as 51.5% and 79.1% at stirring speeds of 0 and 1000 rpm at 150 min.Öğe Organic pollutant removal from edible oil process wastewater using electrocoagulation(Iop Publishing Ltd, 2018) Sharma, Swati; Can, Orhan Taner; Hammed, Monsur; Nawarathna, Dharmakeerthi; Simsek, HalisWastewaters generated from vegetable oil industries contain a high concentration of organic pollutants that are detrimental to the aquatic ecosystem. Electrochemical processes are gaining importance in the treatment of inorganic and resistant organic pollutants in wastewaters. In this study, electrocoagulation (EC) was applied to remove organic pollutants and oil and grease from canola oil wastewater using aluminum (Al) and iron (Fe) electrodes. The application of EC in the wastewater achieved more than 80% removal of organic carbon and nearly 100% removal of suspended solids (SS). The effectiveness of EC is influenced mainly by current density, pH, electrolyte (NaCl), electrode contact time and electrode type. It was observed that Al electrode combination yielded better removal at a lesser time compared to that of Fe electrodes. However, varying current densities had its significance in terms of coagulation time only. Increase in current density achieved decrease in coagulation time. Both Al and Fe could remove between 52-59% of oil and grease from canola oil wastewaterÖğe Peroxydisulfate activation by in-situ synthesized Fe3O4 nanoparticles for degradation of atrazine: Performance and mechanism(Elsevier, 2020) Keyikoğlu, Ramazan; Karataş, Okan; Khataee, Alireza; Kobya, Mehmet; Can, Orhan Taner; Soltani, Reza Darvishi CheshmehHerein activation of persoxydisulfate (PDS) was achieved by in-situ synthesized Fe3O4 nanoparticles (NPs) from a sacrificial iron anode in an electrochemical (EC) cell. The as-synthesized Fe3O4 NPs were characterized to be in spherical and in the nano size. The performance of the process, EC-Fe3O4/PDS, was investigated in terms of atrazine (ATZ) degradation. Optimum process conditions were determined as initial pH of 5, electrolyte (Na2SO4) concentration of 1 mM, a current density of 1.67 A m(-2), PDS concentration of 0.5 mM and initial ATZ concentration of 10 mg L-1. At optimum conditions, the EC-Fe3O4/PDS process could effectively degrade 80% of ATZ in an aqueous solution within a short reaction time of 20 min. The electrical energy consumption of the process was found to be quite low with 0.0307 kWh/m(3). Based on the LC/MS analysis, the degradation pathway of ATZ with seven transformation products was proposed. Finally, a possible mechanism of the EC-Fe3O4/PDS process was put forward, which includes the activation of PDS and the role of radicals in the degradation of ATZ. In conclusion, the combination of Fe3O4 NPs catalyzed PDS oxidation with the EC process was very effective in the degradation of ATZ to dechlorinated final products. The strong synergistic effect makes this process superior to conventional methods due to the high degradation efficiency with low electrical energy and chemical consumption. Application of this method, with very low current density, may not only minimize the electrical energy consumption but also help reduce the sludge production due to the lower iron dissolution.Öğe Phosphorus removal from domestic wastewater in electrocoagulation reactor using aluminium and iron plate hybrid anodes(Elsevier Science Bv, 2018) Omwene, Philip Isaac; Kobya, Mehmet; Can, Orhan TanerThe aim of this study was to investigate the effects of initial pH (pH(i) = 4.0-7.0), current density (j = 10-40 A/m(2)), initial phosphorus (P) concentration (C-i of 5.01-52.13 mg/L) and electrocoagulation (EC) time (t(Ec) = 10-100 min) on phosphorus removal from domestic wastewater by a batch EC reactor using hybrid aluminium (Al)-iron (Fe) anodes and titanium cathode. Phosphorus removal from domestic wastewater containing 52.13 mg/L PO4-P was obtained to be 99.99% at optimum conditions (pH(i) = 4, j = 20 A/m(2) and EC time = 80 min). The energy and electrode consumptions at optimum conditions were calculated as 3.422 kWh/m(3) and 0.328 kg/m(3), respectively. The amount of removed P per electrochemically dissolved total metal electrode (q(e)) was calculated as 55.69 mg P/g, while the dissolved metal to removed phosphorus ratio (M-e/P, mol/mol) was 4.40 (Fe/P = 2.63 and Al/P = 1.77) at optimum conditions. It can be concluded that phosphorus removal by hybrid Al-Fe anodes is as effective as using only Fe or Al anodes as per the results present in literature. In addition, the effluent pH after EC treatment process at optimum conditions was 8.8, hence requiring no pH adjustment before discharge.Öğe The role of dye molecular weight on the decolorization performance of the electrocoagulation(Springer, 2021) Keyikoğlu, Ramazan; Can, Orhan TanerComparative results of color removal performances of Reactive Blue 198 (RB198), Reactive Yellow (RY145) and Reactive Blue 19 (RB19) by electrocoagulation process are presented. Our primary objective was to investigate whether the dye molecular weight affects color removal performance. Dye removal costs of each dye were calculated and compared. Experiments were performed at current densities of 1.04, 2.08, 4.17 and 10.42 A/m(2) in electrocoagulation (EC) reactor with aluminum electrodes connected parallel monopolar configuration. Laboratory-scale experiments were run in batch mode with 0.5 L synthetic dye solution volume and 50 mg/L initial dye concentration. Results showed that the color removal efficiencies were directly influenced by the molecular weight of the dyes. The color removal efficiency of the dye with the greatest molecular weight (RB198) was the highest, whereas the color removal efficiency of the dye with the smallest molecular weight (RB19) was the lowest. Moreover, results indicated that the operating cost of RB198 was significantly lower (2.91 $ per kg dye removed) than RY145 (6.61 $ per kg dye removed) and RB19 ($6.72 per kg dye removed) at a current density of 4.17 A/m(2).Öğe TOC and COD removal from instant coffee and coffee products production wastewater by chemical coagulation assisted electrooxidation(Elsevier Science Bv, 2019) Can, Orhan Taner; Gengec, Erhan; Kobya, MehmetThis paper describes and discusses an investigation into the treatment performance of Boron-Doped Diamond (BDD), N coated Ti (N) and various Mixed Metal Oxide (MMO) anodes after pre-treatment chemical coagulation for total organic carbon (TOC) and chemical oxygen demand (COD) removal from instant coffee and coffee products production wastewater. Firstly, the performance of coagulants, AlCl3,Al-2(SO4)(3), FeCl3 and FeSO4 were investigated. Secondly, the treatment performance of BDD, N and various MMO anodes, the influence of the applied current density and the effect of flow rate for the best-performed electrode were investigated. Also, specific energy consumptions and anode performances were calculated and evaluated for electrooxidation process. At the pre-treatment, among the four coagulants, AlCl3 showed the best performance removing 29% TOC and COD 55%. At the electrooxidation process, BDD electrode achieved the best performance. At the end of the 6 h run period, BDD electrode achieved 95% TOC and 97% COD removal. On the other hand, N and MMO electrodes just removed 13-22% TOC and 25-50% COD respectively. In this study, the BDD electrode performed much better than N and MMO electrodes.Öğe Treatment of intermediate landfill leachate using different anode materials in electrooxidation process(Wiley, 2021) Can, Orhan Taner; Gazigil, Leyla; Keyikoglu, RamazanThis study aims to investigate the performances of widely used anode materials in the treatment of intermediate landfill leachate treatment by electrooxidation (EO) process. The raw leachate was collected from an 8-year-old landfill facility and had a chemical oxygen demand (COD) of 4660 mg/L, biological oxygen demand (BOD5) of 1370 mg/L, and total organic carbon (TOC) of 2260 mg/L. TOC and COD removal efficiencies of Boron-Doped Diamond (BDD), Pt, and four different Ti-based mixed metal oxide (MMO) anodes ((RuO2-TiO2, RuO2-IrO2, PtO2-IrO2, and IrO2-Ta2O5) were compared at the current densities of 25 mA/cm(2), 75 mA/cm(2), and 125 mA/cm(2). At the highest current density, the BDD achieved 100% TOC and COD removal efficiencies in 240 min. BDD was followed by the Pt anode, which achieved 95.53% COD and 92.74% TOC removal efficiencies. The Pt electrode also had the lowest SEC values at all current densities. Although the performances of four MMO electrodes were very close, RuO2-TiO2 achieved a slightly higher performance than the others. It was concluded that Pt anode can be a promising alternative to BDD, which was 18 times more expensive, with its comparable pollutant removal performance and low specific energy consumption.
